Telephone repeater-circuit.



C. A. KRUGKOW. TELEPHONE REPEATER CIRCUIT.

APPLICATION FIIIED JUNE 10, 190 7.

Patented Apr. 25, 1911.

ZILtypes as may be readily iinrrnn at at CARL AUGUST KRUCKOW, OF HALLE-ON-THE-SAALE, GERMANY, ASSIGNOR OF ONE- HALF TO MCMEEN & MILLER. OF CHICAGO, ILLINOIS, A GOPARTNERSHIP.

TELEPHONE REPEATER-CIRCUIT. I

Specification of Letters Batent.

Patented Apr. 25, 1911.;

Application filed June 10, 1807. Serial No. 378,231.

To all whom it may concern:

Be it known that I, CARL AUGUST Km'oimw, a subject of the Emperor of Germany, residing at Halle-on-the-Saale, Germany, have invented a new and useful Improvement in Telephone Repcater-(ir .-i1its, of which the following is a specification.

My invention pertains to circuits for telephone repeaters, rather than to any mechanical devices which have been designed or which may be designed, the mechanical requirements for my circuit consisting of (first) a mechanism adapted on its receiving side to accept speech currents, and adapted on its transmitting side to vary a resistance in response to the accepted speech currents, and (second) an aggregation of induction coils, condensers and batteries of ordinary types of apparatus or of such specialized appreciated from the following description.

The repeater installations hitherto known for long distance lines sufi'er from defects chiefly as follows: 1. They disturb the balance in the two branches of the line. The alternating currents generated by the repcatcr'distribute themselves equally in both directions upon the long distance lines con nected tor the purpose of transmission. 3. The talking currents generated by the microphone of the first station may pass over the whole circuit to the second station: the currents generated by the repeater superimpose themselves upon the former ones and thus produce difference of phase and similar dis turbances.

In the installation presented by Shreeve in United States Patent 791.656. June ('1, 1905, the first detect has been eliminated, but the two others remain. The speech currents coming from either station may pass over the whole circuit to the other station and have superimposed upon them the currents generated by the repeater. In the system proposed by me, I believe I have over come all these defects.

This description is accompanied by two figures, of which- Figure 1 shows in rather diagrammatic form the mechanical repeating device disclosed by Shreeve in United States Patent 791,655, .lune't'i, 1905, and Fig. 9. shows my improved repeater circuits utilizing two of the devices of Fig. 1.

It is of course understoodthat thedevice resents a line 11 which may of Shreeve is shown in Fig. 1 and is referred to in Fig. 2 because it is adapted to the requirements of my circuits, but not because my circuits involve any requirements limiting them solely to the Shreeve device.

In Fig. 1, 1 is apermanent magnet; 2 is a helix of wire wound upon a spool and supported upon the magnet 1 by the case 3 which is attached by screws passing through the magnet. The helix 3 is wound upon the hollow non-magnetic core and an extension pole piece 4, attached adjustably to the magnet 1 by screw threads and provided with the loci: nut 5, forms a terminal for the magnet 1 lying within the helix 2 and approxi-' mately near the center of the helix. Upon the other end of the magnet 1 is supported the granular carbon cell (3. the diaphragm 6' of this cell carries an electrode to which is attached a soft iron rod 7 which extends into the tubular core of the helix 2 and which approaches the pole piece 4. The part. 7 is mechanically free from the core or shell of the helix 2 but is under the considerable magnetic pull from the pole piece 41, due to the permanent magnetism of the magnet 1. This magnetic pull places a tension upon the diaphragm 6. In placing the device in operation the incoming line circuit is connected with the helix 2 and the carbon cell 6 is connected in series with a battery and an induction coil primary, the induction coil secondary being taken to the line upon which the repeater currents are to be sent out. The operation is that speech waves in the helix 2 will vary the attraction between the parts 4- and 7, resulting in a movement of the part '7 and a consequent variation in resistance of the carbon cell 6. which will vary the currentfrom the battery. flowing through the primary of the induction coil, to reproduce in the secondary currents essentially duplicating the speech currents received. .his action is well understood, and I have illustrated only the mechanical device of Fi 1.

T n Fig. 2 I present my repeater circuit devices of Big. 1 shown at 10 and The circuit of Fig. 1 repbe hereinafter as the first line, and a line 21 be hereinafter referred to as the The first line 11. in associated with two 20 respectively.

referred to which may second line.

with an induction coil 12 having three windings, a primary 12, a sec0ndary'12" and an dclitouul Winding or l'ci'l'imy 12, the lim 'l'l 'ciaied with the induction coil 22 by conneclion with its scconlury 'wluiiliug :22". Two

additional im'lucl'ion coils l3 and 9 2:11; pm

Yidccl, R8zlSSOIflzll4-(lE- 3 Il)il(,ll1Ell) Willi can-l1 n the two lines. vi amirng of the winnings 12' 12" 12 is; arbitrary ml some thmighls and 'formuluup; Hl in more syuuueti icnl form when ii? is numccl film" secondary and 12 the tertiary winding, in View oi? the fact that 13 and 225i am not usccl and may ho dispensed Willi, lcziviu 8 mid 23" the true secomlai'ies OJ: iuclucaonums 13 21ml hocause not involved in circuits, the thircl Win-clings oi thosc iuductoriums are not lahelecl in the figure *oi' convczuiencc in the pmcticul applica tion of my cii'uiis, l maize the four.- induction coils mccl'iaiiiczilly ulikc Batteries arc shown at 14k and 24 and con lcnsc'cs at and 25. The condensers-ore p 'eismhlv oi very small capacity, as thcii funciioii is the absorption of very small oscillations and if of abnormally largo capacity they cxerciso a harmful rail-er l'hon beneficial In the rcpezitcrs 1G and 53 1 10" and 520 are lhc rccciving l'ieliccs and i0 20" are the sociatecl carbon cells.

The inductive relations of tho windings upon the induction coil, cores are, as is the usual practice, assumed to be such that, with the primary current flowing downward an increase in the primary current will induce asecondary current firm n upward, in. both of the Ollie? windings 0 he coil.

If we follow the speech currents from line 1-1 We shall find that the transmission proceeds from 12" a primary to 12 the induced currents of 152 flowing through 10 and 13 thus producing in ill) variation of the resistance of 10 which 'VflliOS the current from battery 2 bin-(nigh primary \yiml ing 22, the variation in the current producing in 22 spocch QHICL his which are transmitted over the line 21. TliQCliCU'il of Fig. 2 is symmcl iiclil, and speech cumeuis received from. line arc repealed into line 11 in a manner syz mnctrical Willi the paths uslv fro cod.

In the above transmission (livers local currents and potcnlials were g'll'ffklllttlw The originalh recei'vcd speech cur-rents in 12 produced some o'scilioiiions in the Winding 12"?- uml the curl-c t :h-ou'i. 12 through 10" ag-ii produce 1mm 1 some oscillations in the circuit 13. Th: oscillzilions in 12' and 13 oppose c i l Ul'i'ifll with some clili'cronce of phase and 'lihe of f .c small condenser qui'oiis this 'piriznary cu ii -(lislurbziiuce. Tl'lc pass lhereforc comi urc form to thc helix and arc. u'ieclmi'iiclilly 'lilzinsmiti ccl to the carbon cell 10 Variation iii thc cal-hon cell .10 miu cs flucluatious in WlIlCling's 2'2 and '33 which induce potcntials in 22 [Hill 23 out inasmuch asl'licsc two Winch ings are coumc'l'ecl in opposition fzo each fil llQf (ufcut will not flow in the circuit mu'lniuu hence, will. be no 5; nsu'iitiz d from to a :on primary cii'ci t ontainiiig elc- H 12" and .lfi'will not be dis milieu h an rciicliormry ciijcct attendant upon. flu Ci curl-ems in winding 12'' mm:- uullwl will that spcccli currents receiveclby L I 4 ilic fl'l l ouch Willi m' to ihc (illicit; this re pcafci' vi uii: links mg olliwihe lines; 01' the poi'l'iou v. pails oi ilio lulu: over which ijrzu'ismi n 1-; lo he cficclcrl. The hunts? lion oi? \hc repeater alone WllllOlli; spccialw 12ml circuit has 173 llS adaptability to lepeal; or transmit in one clu'cctiou only. The spociul circuit my (lQVlCG provides a separate i'c iieutcr for i'c'pcziiing in each clirection anci pics ides IliBHl'lZlllZlRg means whereby the remalnnoii saliva is IQSU'RUJGCl i-ZE'OH). deletci'ious (Tc/ct upon the operating elcments of u thus described my invciibiomwhah l lzmu 5.5 UQW and desire to secure by United Hluz'cs llvllci's Potent is:

l in u lclo 'aliouc repeater circuit, a. symmetrical ll'KllH'llVO link each half of said link -;l.111'1'l l1lf l'hc Following clcments:two imluclion coils; a. circuit containing in series 2| wiurl' of each of said induction coils, a hath. i :iucl u variable resistance controlled by (he lu fluoiivc helix of the other half; and n-sccoml circuil containing in series a Winding of such of said induct-ion coils and an inductive hclix controlling rhe variable resis-[u mice of file other half.

In a lclephonc repeater circuit, a symmetrical imlucl'ivii link having two 'rcpeaiting rjlc'viccseach half of said linl: COI'IIPI'lS- lug; ihc "Hlouinp clcmcnl s:---lwo induction circuit c uiainiu o in s I'll-S {L Windii'uiucliou coils, a huttcirv inductive liclix of the. Olll i lll-IGl19l losicle tone in tho ci'. lone substation circuit. It; ho swan, llllll lll'l-l lllfll'i all local or re wurrcnls ucutmlizcd or an "f" are transmitted through :"sluncc conli-ollml by the y 3. In a telephone repeater circuit, a symmetrical inductive link each half of which comprises the following elements :-two induction coils; a circuit containing in series a primary winding of each of said induction coils, a battery, and a variable resistance controlled by the inductive helix of the other half; and a second circuit containing in series a windin of each of said induction coils and an in active helix controlling the variable resistance of the other half, said winding being connected in opposition with reference to potentials resulting from currents from said battery.

4. In a telephone repeater circuit, a symmetrical inductive link having two repeate s and each half of which comprises the following elements: two induction coils; a circuit containing in series a primary Winding of each of said induction coils a battery, and a variable resistance controlled by the inductive helix of the other half; and asec- 0nd circuit containing in series a winding of each of said induction coils and an inductive helix controlling the variable resistance of the other half, said winding being connected in op osition with reference to potentials resulting from currents from said battery.

5. In a telephone repeater circuit. a symmetrical inductive link having two repeaters and each half of which comprises the following elements: two induction coils; a circuit containing in series a primary winding of each of said induction coils, a battery, and a variable resistance controlled by the inductive helix of the other half; and a second circuit containing in series a winding of each of said induction coils and an inductive helix controllin the variable resistance of the other hal said windings being connected in opposition with reference to potentials resulting from currents from said battery; and a line circuit of two parts, 5

each part directly connected to the terminals of a third winding 'of one of the induction coils of each of said halves, respectively.

6. In a telephone repeater circuit, a symmetrical inductive link having two repeaters and each half of which comprises the following elements: two induction coils; a circuit containing in series a primary winding of each of said induction coils, a battery, and a variable resistance con rolled by the inductive helix of the other half; and a second cireuit'containing in series a winding of each of said induction coils and an ingductive helix controlling the variable resistance of the other half, said winding being connected in opposition with reference to potentials resulting from currents from said battery; a line circuit directly connected to the terminals of a third winding of one of the induction coils; and a condenser connected as a shunt around the primary winding of the last mentioned induction coil.

link connecting the same, each I 7. In a telephone repeater circuit, a symmetrical inductive link connecting two coni ductively isolated portions of a telephone l line and comprising four induction coils, i two of said induction coils pertaining to leach line portion; two windings for one of l said coils; a primary, a secondary and a tertiary winding for one of said coils, said secondary being connected to its line portion and said tertiary and a corresponding winding of its associated coil being connected in opposition.

8. In a telephone repeater circuit, a symmetrical inductive link connecting two conductively isolated portions of a telephone line and comprising four induction coils, two of said induction;coils pertaining to each line portion; two windings for one of said coils; a primary, a secondary and a tertiary winding for one of said coils, said secondary being connected to its line portion and said tertiary and a corresponding winding of its associated coil being connected in series with each other and with a receiver helix and in opposition to each other.

9. In a telephone repeater circuit, an inductive link having an inductive receiving circuit consisting of two secondaries and a repeater helix, the two secondaries being opposingly connected with reference to their respective primaries and one of said secondaries being inductively related to a winding associated with a telephone line, and whereby speech currents generated in one of said secondaries through its inductive relation with the telephone line may flow through both of said secondaries and through the repeat-er helix, and whereby potentials generated in said secondaries by a current through their respective primaries will oppose and neutralize and will not result in current through the repeater helix, substantially as described.

10. In a telephone repeater circuit. a transmitting circuit containing a variable resistance, a battery and two inductive primary coi each of said primary coils having a secondary and said two secondaries being connected in opposition and in series with a repeater receiving helix. and one of l said primary coils having an additional inductive winding as o iated with the telephone circuit over which transmission is dc-. sired, substantially as described.

ll. In a telephone repeater circuit. a transmitting circuit containing a variable resistance, a battery and two inductive primary coils: secondary primary coils; and upon one of said primary coils an additional secondary coil said secondary coil being connected across the line over which transmission is to be effected.

12. in a telephone repeater circuit. two

parts of line; and a symmetrical inductive half of coils for each of said variableresistance controlled by the inducother; each of said halves comprisinga. '70 tive helix of the other half; and a second transmitting circuit, containing the variable circuit containing in series a, winding of resistance, a hatter; and twdpriniary ineachof said induct-ion coils, cud an induc ductive windings; a small condenser as a tire helix controlling the variable resistance shunt about one of said. primary windings; of the other half. and a receiving circuit. containing a receiv- 13. In. a telephone repeater circnit,-two l ing helix and the secondaries of said pri-' parts of a' line; two repeaters and a svin mary windings, said secondaries being coninetrical inductive link of two halves. each I nected in opposition. 7 half comprising the following elements: two i 18. In a telephone repeater circuit, a sym in duetion coils: a circuit containing; in series I et i C Ct VQ lint? 6 6 l of 82 M 0 a primary winding of each of said induction link comprising the following elements: coils, a battery and n ni'inl' lc resi tance two indut-tion coils; a circuit containing acontrollcd by the inductive helix of the other i ind g Oi Each of Said induction coils, a half; and a second circuit containing in battery, and a variable resistance controlled series a winding of each of said induction by the inductive helix ofthc othcrhalf; and 5 coils, and an'inductivc'helix controlling the SOCOT'Kl Circuit?- fiolltfiifllillg' i Winding 0f variable resistance of the other half: .the 1 O S d inthlction Coils and an inductive windings being in oppoaitionupon said helix hBliX g e v riahl jresistance Of 1-1-. In a repeater circuit. an inductive the other half, said two circuitsheing iii-' link of two halves, each half cmitaining a c ively n u ral e h p n e hn. receiving helix and a variable resistance, the 19.111 ph ne repea er c i'cuit, l $37111- helix of one half controlling the resistance fit c uct e l nkhaving two repeating of the other; each of said halv c i i I devices, such half of said link comprising a transmitting circuit, cont i i th thefollowing ele1nents1tWo'induction coils; rialole resistance, a battery and two' rim a, circuit containing a windingof each of 5, inductive windings; an inductive winding saidinduotion coils, a hatter and a variable upon one of said primaries to which the line r sis ance controlled by theinductivc helix circuit is directly connected; nnd 'a recgivofjtvhe other half; and a second circuit coning circuit containing a receiving helix and M n ng a winding of eaclroi? said induction the secondaries of said primary Windingg, coils and an induetl e helix ,controllmg the said secondaries being connected in opp0sivflriflhle'reslstame f other ha B d tion. f' two circuits being inductively ,neutral each 15. In a repeater circuit an 'inductivelink upon the others l f C of two halves, each half containing a rehc'iv .20.- 1n a. telephone rcpez ter circuit, a sync: I i n h li d a i bl r i t th metrical inductive link; each half of said heir' of one half controlling the resistn c p g" e following em ance of the other; each'oi said halves conr i u n coils; FL fiilcuit contammg prising a transmittingcircuit, containing w d g of web Said indufifioil fibils, the Variable resistance a battery and two a ry n v rl l re i tanc -con rolled; primary inductive windings; a condenser as by the inductive heli r of the other half; a i a shunt about one of said primary windings second clrcult contain ng a winding, of each and a receiving circuit containin a receivofsaid induction coils and an gl-DdllCtlVG. ingi helix and the secondaries 0' said pri-. hell-Y c n o l g the valjlable i fi fi m tp niary windings, said secondaries being con the other half, Sold two clrcults bemg lndud nected in opposition. 'tivelv neutral each upon the other; end an 16. In a repeater circuit, an inductive link addltlonal Wlndmg upon 011? Oi So d Induce of two halves, each half containing a receivtion coils and associated with aftelcphonc ing helix and a variable resistance, the helix line. 5 L f of onchalf controlling the resistance of the 21. In a-telephone repeater circuit-,a sylnother; each of said halves comprising 21- metriccl inductive link eachhalf ofwhlch 1'20 transmitting circuit, containing the variable t coinprises the following eleinentszg'a" p luresistance, a battery and two primary inl rality of 1nductor1ums; a. c rcuit conta ning ductive windings; a condenser us a. shunt I primary windings of rnductgriums, a hat- 7 about one of said primary windings; an intery, vgiriahlc resistancc controlled by ductive winding upon one of said primaries the receiving hel x or the other helflund 1111 25 to which. the line circuit is directly con- [second circuit containing windings of in nected; anda receiving circuit containing a l ductoriums and the rcceiving heli scor' tro'lreceiving helix and the secondaries of said hug the variable resistance of thc ot her halr, I primary windings, said secondaries beingsaid circuits being connected Inductively connected in opposition. l neutral upon each other. i 13c said symmetrical liiilc comprising the following elements: two circuit containing in series a winding of each of said induction coils. a battery and a induction coils; a5

I scones 17. In a repeater circuit, an inductive link of two halves, each half containing a receiving helix and a variable resistance, the helix of one half controlling the resistance of the mary coils; upon one of 22. ln a telephone repeater circuit, a symmetrical inductive link having two repeaters and each half of which comprises the following elements: a plurality oiiinductoriums; a circuit containing primary windings of inductoriums; a battery and a variable resistance controlled by the receiving helix of the other half and a second circuit containing windings of inductoriums and the receiving helix controlling the variable resistance of the other half, said circuits being connected inductively neutral upon each other.

23. In a telephone repeater circuit, a symmetrical inductive link each half of which comprises. the following rality of inductoriums; a circuit containing primary windings of inductor'ium's, a battery and a variable resistance controlled by the receiving helix of the other half; and a second circuit containing windings of inductoriums andthe receiving helix con trolling the variable resistance of the other half, said circuits being connected inductively neutral upon'each other; aid 21 line winding in tively' related to both of saidcircuits. 24. In a telephone repeater circuit, a transmitting circuit containing a variable resistance, a battery and two inductive primary coils; secondary coils for each of said primary coils; upon orie or said primary coils an additional secondary coil to the terminals of which is directly connected the line over which transmission is to be etiected; and, a circuit including a receiving helix and the two first mentioned secondaries, the secondaries being so related'inductively to said primaries as to produce no current in said receiving helix in response to the operation of the primaries.

in a telephone repeater circuit, a transmitting circuit containing a variable resistance, abattery and two inductive primary coils; secondary coils for-each of said primary coils; upon one of said primary coils an additional secondary coil to the terminals of which is directly connected the line over which transmission is to be reflected; and upon the same primary coil a condenser con- 'nected as a shunt.

526. In a telephone repeater circuit,atransmitting circuit containing a variable resistance, a. battery and two inductive primary coils; secondary coils for eacn of said pri said primary coils an additional secondary coil to the terminals of which is directly connected the line over which transmission is to be eii'ected; and upon the same primary coil a small condenser connected as a shunt.

27, in a telephone repeater system, the,

elements: a plu an inductorium and induc- 'is prevented by ,nctic eilects'irom operation by thelocal or combination with a line circuit and a pri mary circuit, of a repeating device having I two windings, one jot saidwindings bein inductively connected with said line and primary circuits, and the other of said windings being inductively connected with the said primary circuit only. p

28.;In a telephone repeater, in combination, two independent line circuitsassociated for repeater service, two repeating devices, one for each respective line circuit, each repeating device comprising areceiver and a transmitter, a windin ineach line circuit to control the respective-repeating devices and actuating them by the inward or re ceived currents, a balancing auxiliary or local circuit for eachrepeatin device, dif-J' terential means-in each balanclng auxiliary circuit for eacli repeating device controlled by the'transmitter of the opposite repeating device, a primary circuit for each repeating device, and an induction coil with primary, tertiary and secondary windings for each, line circuit inductively associating the re spective primary, balancing and line circuits.

29. In a reciprocal telephone repeating systennthe combination with two telephone lines or circuit sections of two repeating telephones,

means for inductively associating and identifying the receiver of each repeater with a respective circuit section, and means for balancing each re eater locally to prevent react-ive transmission, an individual local circuit for the transmitter of each repeater together wit 1 means for jointly inductively associating each said transmitter with the opposite line circuit section and with its receiver.

' 80. In a telephone repeater system, the combination with a main telephone-circuit, of arepeating device anda tertiary circuit in which the repeating device is connected and is directly inductively associated with said main-telephone-circuit, a primary or transmitter-circuit which is also directly inductively connected with the said main circuit and with the tertiary circuit, and, means for an extra or auxiliary inductive co'nnection directly between the tertiary, and primary circuits, whereby the repeating device differential current or magrepeated currents, "yet is operated by the received or initial main clrcuit currents.

Signed at Berlin, Germany, on the seventeenth day otMaj A. D. 1907, in the presence of two witnesses.

CARL AUGUST KRUCKOVV.

.Vitnesses HENRY Hasrnn, Wonnnrran HAUPT.

llil

"fur inipz'ovemant in Telephone Repeater-Chcuits,

printevl ispmii'fication requiring co rrectiun as foliows: Page 4, line 23,

t is hereby certified that'ir; Letters Patent No. 990,365, granted April 25,1911, u pon the, appiicaatifm of {Earl August Kmclmw, of I-Iai1e-0n- 3he-$aale, Germany,

an cam-6r appears in flu;

aftar file and that the said Letters Patent should be read-"With this correction therein that mama may conform to the record pf the case in the Patent flficg.

Sigma and-salad this 6th day of Jufi, A. 9., 1911.

c. a. BILLINGS, i 

